CFD modelling of the microclimate of a cultivated greenhouse: A validation study between experimental and numerical results

Abstract

In this work, we present the validation of a numerical model of a greenhouse thermally in-sulated on three sides with a tomato crop. A CFD software (Ansys-Fluent) was used to solve the numerical model. The discrete ordinate model was included to solve the radiative trans-fer equation. The results of the numerical model were compared with the values of air tem-perature observations at different points in the greenhouse. Good agreement was obtained between the simulated and measured values, with coefficients of determination R2 = 0.77, R2 = 0.84, R2 = 0.99, and R2 = 0.89 for the temperatures of the points 10 cm, 80 cm, and 210 cm above the ground and the average temperature in the greenhouse, respectively. A third-order polynomial curve was drawn between the simulated and measured values of relative humidity in the greenhouse. These R2 values are 0.9786 and 0.7165, the simulated and measured relative humidity, respectively. The simulation results showed low velocity values with an average of 0.525 m/s located between 1.5 m and 2 m from the ground.

Keywords

• CFD Modelling
• Validation
• Greenhouse
• Plant
• Radiation Model (Discrete Ordinate)
• Ansys-Fluent

References

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